Phillip Seaton went to the hospital in October 2007 for a routine circumcision to treat inflammation but left the operating room without a penis.

Seaton sued his surgeon, Dr. John Patterson, for removing his penis without his permission, and the trial got under way Monday in Shelby County (Kentucky) Circuit Court. Seaton and his wife, Deborah, seek damages for "loss of service, love and affection."

But Patterson said he found cancer while performing the routine circumcision, and Patterson's defense attorney, Clay Robinson, said the surgeon had no other options but to remove the penis immediately, according to court documents.

The tip of Seaton's penis "had the appearance of rotten cauliflower" because it was so inundated with cancer, Robinson told the courtroom, according to the AP.

Judge Charles Hickman instructed both lawyers to refrain from commenting on the case because it is ongoing.

Despite the alleged seriousness of Seaton's penile cancer, experts contacted by ABCNews.com said that the doctor needed consent from the patient before surgically removing his sex organ.

"I think the doctor made a big mistake, and will not win the case," said Dr. David Crawford, a professor of surgery at the University of Colorado Health Sciences Center.

Partial penectomy, or a partial removal of the penis, Mohs surgery, a precise surgery used to remove several types of skin cancer, laser and radiation therapies were all options when treating penile cancer, said Crawford.

Because the surgeon had said the cancer was so severe, Robinson told the courtroom that Patterson could treat it only by surgically removing the organ.

Nevertheless, "a surgical consent is needed to do this," said Dr. Glenn Bubley, associate professor of medicine at Harvard Medical School. "This is the standard of care. There would be no reason to breach standard of care in this case."

Man Sues Doc After Removing Penis Without Consent

Seaton also sued Louisville's Jewish Hospital, where the surgery was performed. The hospital settled out of court for an undisclosed amount.

While Bubley said that the only curative option for some penile cancer cases was to remove the penis, "he needed to [give consent]. ... Patients have the right to say no to even curative treatment. That's why the hospital settled."